So far, I managed to take the top off and assemble it back, as a first exercise. Harder than it looks, because there is a flash sensor pin must be just inserted in the hot shoe for the top to fit.
This is how the Kiev 35A looks with the top off.
As I have no idea of the mechanisms and could find no diagram or coherent repair instructions, my plan was to disassemble, look and learn. Am open to suggestions!
In order to look at the film transport, I believe that I should take off the disc of the film counter. The assembly seems to be fixed by the screw pointed by the green arrow. It is very tight and did not want to force it. Maybe it is not even a screw but an axis (?). Should I take out the key around that screw? What tool would be used for that?
Thanks for any comment!